Fractal-tree communication structure and method, control apparatus and intelligent chip

ABSTRACT

A communication structure comprises: a central node that is a communication data center of a network-on-chip and used for broadcasting or multicasting communication data to a plurality of leaf nodes; a plurality of leaf nodes that are communication data nodes of the network-on-chip and used for transmitting the communication data to the central node; and forwarder modules for connecting the central node with the plurality of leaf nodes and forwarding the communication data, wherein the plurality of leaf nodes are divided into N groups, each group having the same number of leaf nodes, the central node is individually in communication connection with each group of leaf nodes by means of the forwarder modules, the communication structure is a fractal-tree structure, the communication structure constituted by each group of leaf nodes has self-similarity, and the forwarder modules comprises a central forwarder module, leaf forwarder modules, and intermediate forwarder modules.

TECHNICAL FIELD

The present invention relates to the technical fields of intelligentdevice, unmanned driving and network-on-chip data transmission, etc.,and particularly relates to a fractal-tree communication structure andmethod, a control apparatus, and an intelligent chip for communicationof a network-on-chip.

BACKGROUND ART

Broadcast and multicast operations are realized on a network-on-chip,wherein the network-on-chip is a new communication method of a system onchip and is a key component of the multicore technology. “Broadcast”means that the network duplicates and forwards data packages sent from abroadcast address unconditionally, and all hosts can receive all theinformation; “multicast” means that multicast data is only received byinterfaces interested in the data package, that is, it is received byinterfaces on the hosts running an application system which intends totake part in a multicast session. The available network-on-chipcommunication technology comprises grid-type network-on-chip and annularnetwork-on-chip.

As shown in FIG. 1, which is a structure diagram of a grid-typenetwork-on-chip, each tile is connected with up, down, left and righttiles, and every two adjacent tiles may transmit data to each otherdirectly. However, such a grid-type network-on-chip structure hasdisadvantages of complexity in controlling broadcast and multicast, anddisunity of desired delay numbers as tiles for transmitting data aredifferent.

As shown in FIG. 2, which is a structure diagram of an annularnetwork-on-chip, all tiles are connected to a ring, and every twoadjacent tiles may transmit data to each other directly. However, suchan annular network-on-chip structure has a disadvantage of longer delayin broadcasting and multicasting.

There is not an effective support to broadcast and multicastcommunication among multiple cores on the chip in the prior art, so itis urgent and necessary to provide a solution of low delay and smalloccupied area that is suitable for the broadcast communication andmulticast communication simultaneously.

DISCLOSURE OF THE PRESENT INVENTION

With respect to deficiencies of the prior art, the present inventionprovides a fractal-tree communication structure and method, a controlapparatus, and an intelligent chip.

The present invention provides a fractal-tree communication structurefor communication of a network-on-chip, comprising:

a central node that is a communication data center of thenetwork-on-chip and used for broadcasting or multicasting communicationdata to a plurality of leaf nodes;

a plurality of leaf nodes that are communication data nodes of thenetwork-on-chip and used for transmitting the communication data to acentral node; and

forwarder modules for connecting the central node with the plurality ofleaf nodes and forwarding the communication data,

wherein the plurality of leaf nodes are divided into N groups, eachgroup having the same number of leaf nodes, the central node isindividually in communication connection with each group of leaf nodesvia the forwarder modules, the communication structure is a fractal-treestructure, the communication structure constituted by each group of leafnodes has self-similarity, and the forwarder modules comprise a centralforwarder module, leaf forwarder modules, and intermediate forwardermodules.

As regards to the fractal-tree communication structure for communicationof the network-on-chip, it may decrease the number of the forwardermodules so as to maximize sharing degree of the forwarder modules, underthe circumstance of ensuring that the central node is in communicationconnection with each group of the leaf nodes individually.

The present invention further provides a communication method forcommunication of a network-on-chip using said apparatus, comprisingbroadcasting or multicasting communication data to the plurality of leafnodes by means of the central node, and transmitting the communicationdata in the network-on-chip to the central node when received by theplurality of leaf nodes.

The communication method for a network-on-chip comprises:

when communication data is broadcasted from the central node to theplurality of leaf nodes, firstly inputting the communication data into adata cache of a central forwarder module of the central node, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into data caches of leaf forwarder modules of the leaf nodes,wherein the leaf forwarder modules output the communication data to theleaf nodes in each group of leaf nodes via output ports.

The communication method for a network-on-chip comprises:

when the central node multicasts communication data to the plurality ofleaf nodes, firstly inputting the communication data into a data cacheof the central forwarder module of the central node, then transmittingthe communication data in data caches of the intermediate forwardermodules sequentially, and finally inputting the communication data intodata caches of the leaf forwarder modules in direct connection with theleaf nodes, wherein the leaf forwarder modules shift the communicationdata in the data caches by means of shifters, distribute communicationdata of preset bandwidth to each of leaf nodes, and output thecommunication data to the leaf nodes in each group of leaf nodes viaoutput ports of the leaf forwarder modules.

The communication method for a network-on-chip comprises:

when the plurality of leaf nodes transmit communication data to thecentral node, if the leaf nodes transmit communication data of fullbandwidth, firstly inputting the communication data into data caches ofthe leaf forwarder modules of the leaf nodes, then transmitting thecommunication data in data caches of the intermediate forwarder modulessequentially, and finally inputting the communication data into a datacache of the central forwarder module of the central node, wherein thecentral forwarder module sums up all received data transmitted from theleaf nodes by means of an adder, and outputs a result to the centralnode via output ports of the central forwarder module.

The communication method for a network-on-chip comprises:

when the plurality of leaf nodes transmit communication data to thecentral node, if the leaf nodes transmit communication data ofrespective preset bandwidth, firstly inputting the communication datainto data caches of the leaf forwarder modules of the leaf nodes, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into a data cache of the central forwarder module of the centralnode, wherein the central forwarder module shifts all receivedcommunication data transmitted from the leaf nodes by means of shiftersaccording to a position of preset bandwidth of the communication data infull bandwidth, sums up all received communication data transmitted fromthe leaf nodes by means of an adder, and outputs a result to the centralnode via output ports of the central forwarder module.

The communication method for a network-on-chip comprises:

after the central forwarder module shifts all received communicationdata transmitted from the leaf nodes by means of shifters according to aposition of preset bandwidth of the communication data in fullbandwidth, setting data beyond the preset bandwidth of the communicationdata transmitted from each of the leaf nodes to be 0 by means of fixedlogic units in the central forwarder module to execute subsequentsummation operation.

The present invention further provides a control apparatus comprisingone or more said communication structures connected by means offorwarder modules.

The present invention further provides an intelligent chip comprisingsaid control apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structure diagram of the grid-typenetwork-on-chip.

FIG. 2 is a schematic structure diagram of the annular network-on-chip.

FIG. 3 is a schematic diagram of a multicore on chip structure with 16+1cores connected using a H-tree in one embodiment of the presentinvention.

FIG. 4 is a schematic structure diagram of a hub in one embodiment ofthe present invention.

FIG. 5 is a schematic structure diagram of hub_one_to_two used in oneembodiment of the present invention.

FIG. 6 is a schematic structure diagram of hub_two_to_one used in oneembodiment of the present invention.

FIG. 7 is a schematic diagram of an action of the hub when transmittingfrom one core to multiple cores for broadcasting in one embodiment ofthe present invention.

FIG. 8 is a schematic structure diagram of transmission from one core tomultiple cores in one embodiment of the present invention.

FIG. 9 is a schematic diagram of an action of the hub not in directconnection with leaf tiles when transmitting from one core to multiplecores for multicasting in one embodiment of the present invention.

FIG. 10 is a schematic diagram of an action of the hub in directconnection with leaf tiles when transmitting from one core to multiplecores for multicasting in one embodiment of the present invention.

FIG. 11 is a schematic diagram of an action of the hub when outputs ofthe multiple cores are added, and transmitted to one core in fullbandwidth in one embodiment of the present invention.

FIG. 12 is a schematic structure diagram of data transmission whenoutputs of the multiple cores are added, and transmitted to one core formulticasting in one embodiment of the present invention.

FIG. 13 is a schematic diagram of an action of the hub not in directconnection with leaf tiles when outputs of the multiple cores are bitspliced, and transmitted to one core in preset bandwidth in oneembodiment of the present invention.

FIG. 14 is a schematic diagram of an action of the hub in directconnection with leaf tiles when outputs of the multiple cores are bitspliced, and transmitted to one core in preset bandwidth in oneembodiment of the present invention.

FIG. 15 is a schematic diagram of implementing bit splice in oneembodiment of the present invention.

FIG. 16 is a schematic structure diagram of a multicore on chip of 16+1cores connected using a X-tree in another embodiment of the presentinvention.

FIG. 17 is a schematic structure diagram of a Hub in another embodimentof the present invention.

FIG. 18 is a schematic structure diagram of hub_one_to_four used inanother embodiment of the present invention.

FIG. 19 is a schematic structure diagram of hub_four_to_one used inanother embodiment of the present invention.

FIG. 20 is a schematic diagram of an action of the hub when transmittingfrom one core to multiple cores for broadcasting in another embodimentof the present invention.

FIG. 21 is a schematic structure diagram of transmission from one coreto multiple cores in another embodiment of the present invention.

FIG. 22 is a schematic diagram of an action of the hub not in directconnection with leaf tiles when transmitting from one core to multiplecores for multicasting in another embodiment of the present invention.

FIG. 23 is a schematic diagram of an action of the hub in directconnection with leaf tiles when transmitting from one core to multiplecores for multicasting in another embodiment of the present invention.

FIG. 24 is a schematic diagram of an action of the hub when outputs ofthe multiple cores are added, and transmitted to one core in fullbandwidth in another embodiment of the present invention.

FIG. 25 is a schematic structure diagram of data transmission whenoutputs of the multiple cores are added, and transmitted to one core inanother embodiment of the present invention.

FIG. 26 is a schematic diagram of a no shift and no mask action of thehub not in direct connection with leaf tiles when outputs of themultiple cores are bit spliced, and transmitted to one core in presetbandwidth in another embodiment of the present invention.

FIG. 27 is a schematic diagram of an action of the hub in directconnection with leaf tiles when outputs of the multiple cores are bitspliced, and transmitted to one core in preset bandwidth in anotherembodiment of the present invention.

FIG. 28 is a schematic diagram of implementing bit splice in anotherembodiment of the present invention.

PREFERABLE EMBODIMENTS

In order to solve the above technical problem, the present inventionprovides a fractal-tree communication structure for a network-on-chip,comprising:

a central node that is a communication data center of thenetwork-on-chip and used for broadcasting or multicasting communicationdata to a plurality of leaf nodes;

a plurality of leaf nodes that are communication data nodes of thenetwork-on-chip and used for transmitting the communication data to thecentral node; and

forwarder modules for connecting the central node with the plurality ofleaf nodes and forwarding the communication data,

wherein the plurality of leaf nodes are divided into N groups, eachgroup having the same number of leaf nodes, the central node isindividually in communication connection with each group of leaf nodesvia the forwarder modules, the communication structure is a fractal-treestructure, the communication structure constituted by each group of leafnodes has self-similarity, and the forwarder modules comprise a centralforwarder module, leaf forwarder modules, and intermediate forwardermodules.

Under the circumstance of ensuring that the central node is incommunication connection with each group of the leaf nodes individually,the number of the forwarder modules is decreased, such that a sharingdegree of the forwarder modules is maximized.

The present invention further provides a communication method using theapparatus, comprising broadcasting or multicasting communication data tothe plurality of leaf nodes by means of the central node, andtransmitting the communication data in the network-on-chip to thecentral node when received by the plurality of leaf nodes;

when communication data is broadcasted from the central node to theplurality of leaf nodes, firstly inputting the communication data into adata cache of intermediate central forwarder module of the central node,then transmitting the communication data in data caches of theintermediate forwarder modules sequentially, and finally inputting thecommunication data into data caches of leaf forwarder modules of theleaf nodes, wherein the leaf forwarder modules output the communicationdata to the leaf nodes in each group of leaf nodes via output ports;

when the central node multicasts communication data to the plurality ofleaf nodes, firstly inputting the communication data into a data cacheof the central forwarder module of the central node, then transmittingthe communication data in data caches of the intermediate forwardermodules sequentially, and finally inputting the communication data intodata caches of the leaf forwarder modules in direct connection with theleaf nodes, wherein the leaf forwarder modules shift the communicationdata in the data caches by means of shifters, distributes communicationdata of preset bandwidth to each of leaf nodes, and output thecommunication data to the leaf nodes in each group of leaf nodes viaoutput ports of the leaf forwarder modules;

when the plurality of leaf nodes transmit communication data to thecentral node, if the leaf nodes transmit communication data of fullbandwidth, firstly inputting the communication data into data caches ofthe leaf forwarder modules of the leaf nodes, then transmitting thecommunication data in data caches of the intermediate forwarder modulessequentially, and finally inputting the communication data into a datacache of the central forwarder module of the central node, wherein thecentral forwarder module sums up all received data transmitted from theleaf nodes by means of an adder, and outputs a result to the centralnode via output ports of the central forwarder module;

when the plurality of leaf nodes transmit communication data to thecentral node, if the leaf nodes transmit communication data ofrespective preset bandwidth, firstly inputting the communication datainto data caches of the leaf forwarder modules of the leaf nodes, thentransmitting the communication data in data caches of the intermediateforwarder module sequentially, and finally inputting the communicationdata into a data cache of the central forwarder module of the centralnode, wherein the central forwarder module shifts all receivedcommunication data transmitted from the leaf nodes by means of shiftersaccording to a position of preset bandwidth of the communication data infull bandwidth, sums up all received communication data transmitted fromthe leaf nodes by means of an adder, and outputs a result to the centralnode via output ports of the central forwarder module;

after the central forwarder module shifts all received communicationdata transmitted from the leaf nodes by means of shifters according to aposition of preset bandwidth of the communication data in fullbandwidth, setting data beyond the preset bandwidth of the communicationdata transmitted from each of the leaf nodes to be 0 by means of fixedlogic units in the central forwarder module to execute subsequentsummation operation.

The present invention further provides a control apparatus comprisingone or more communication structures connected by means of forwardermodules.

The present invention further provides an intelligent chip comprisingthe control apparatus.

Below are two embodiments of the present invention, and the presentinvention is further explained in detail with reference to the drawings,such that those skilled in the art can carry it out according to thedisclosure.

One embodiment is an apparatus in H-tree structure for communication ofa network-on-chip, comprising: a central tile that is a communicationdata center of a network-on-chip; and a plurality of leaf tiles that arecommunication data nodes of the network-on-chip and in communicationconnection with the central tile by means of hubs, wherein thecommunication connection is set as follows: every two leaf tiles are setas one group, the central tile is individually in communicationconnection with each group of leaf tiles (which include devices relatingto data operation, storage and transmission such as an arithmetic unit,a rain, a controller, etc.) by means of the hubs, and the connectingmanner can achieve high efficient communication.

The number of the plurality of leaf tiles are an even number, and theyuse one central tile (which includes devices relating to data operation,storage and transmission such as an arithmetic unit, a rain, acontroller, etc., wherein the controller is a main controller forcontrolling data transmission and operation of the leaf tiles). Saidsetting way of the nodes facilitates reducing complexity of connection,and is convenient for setting and use of the network-on-chip structure.FIG. 3 illustrates a schematic diagram of a multicore on chip structurewith (16+1) cores connected by an H-tree. In this structure, sixteenleaf tiles and one central tile are connected using the H-treestructure. In addition, it further comprises a plurality of hubs forprocessing and distributing data, so as to transmit data from one coreto multiple cores in a broadcast or multicast form, and transmit data ofthe multiple cores after adding or bit splicing (i.e., splicing to{leaf_tile15_data, leaf_tile14_data, . . . , leaf_tile0_data}) to onecore, wherein the number, function and structure of the related body(i.e., cores to be connected) are not limited.

The communication connection is set as follows: under the circumstanceof not affecting the individual communication connection of the centraltile with each group of leaf tiles, a sharing degree of the hub ismaximized, and the communication connection achieves effectivecommunication to a plurality of nodes, decreases the number of hubs, andreduces complexity of the communication connection, wherein the H-treeis used for connecting respective tiles and is consisted of connectinglines and the hubs among the tiles. FIG. 4 illustrates a structurediagram of a hub. The hub is consisted of a plurality of hub_one_to_twoand a plurality of hub_two_to_one, the hub_one_to_two divides one groupof input into two groups of outputs for transmitting from the centraltile to the leaf tiles; and the hub_two_to_one merges two groups ofinputs into one group of output for transmitting from the leaf tiles tothe central tile.

FIG. 5 illustrates a structure diagram of the hub_one_to_two. Thestructure is responsible for processing one group of input data andforwarding the processed data to two output ports according to controlsignals, and comprises: an input data cache for caching input data, andshifters for shifting the input data and generating output dataaccording to the control signals.

FIG. 6 is a structure diagram of the hub_two_to_one. The structure isresponsible for processing two groups of input data and forwarding theprocessed data to one group of outputs according to control signals, andcomprises: shifters for shifting the input data according to the controlsignals; Mask logics for generating 01 string having the same bit numberas the input data according to the control signals, and performing anAND operation on the 01 string and the input data; an adder for addingthe two groups of input data; and an output data cache for cachingoutput data. A communication method of the apparatus comprises:broadcasting or multicasting from the central tile to the plurality ofleaf tiles; or executing transmitting the communication data from theplurality of leaf tiles to the central tile, so as to provide atechnical support for efficient broadcast or multicast.

When broadcasting from the central tile to the plurality of leaf tiles,the transmission manner of the communication data transmitted from thecentral tile on the hubs is as follows: firstly inputting into a datacache of a central hub in direct connection with the central tile, thentransmitting in data caches of central hubs sequentially, and finallyinputting into data caches of leaf hubs in direct connection with theleaf tiles, wherein the leaf hubs output the communication data to twoleaf tiles in each group of leaf tiles via two output ports directly, soas to achieve broadcast communication via the hubs and the tiles. FIG. 7illustrates a schematic diagram of an action of the hub whenbroadcasting from one core to multiple cores. Since it is one-to-twotransmission, it only uses hub_one_to_two in the hubs, and controlsignals of hub_one_to_two in all hubs are forwarded directly, such thatoutput data equal to input data for each hub_one_to_two. FIG. 8illustrates a structure diagram of data transmission from one core tomultiple cores in the H-tree structure. In the H-tree structure, thetransmission order of data is as follows: from a central tile to ahub_0_0; from the hub_0_0 to a hub_1_x; from the hub_1_x to a hub_2_x;from the hub_2_x to a hub_3_x; and from the hub_3_x to leaf tiles.

When multicasting from the central tile to the plurality of leaf tiles,the transmission manner of the communication data transmitted from thecentral tile on the hubs is as follows: firstly inputting into a datacache of a central hub in direct connection with the central tile, thentransmitting in data caches of central hubs sequentially, and finallyinputting into data caches of leaf hubs in direct connection with theleaf tiles, wherein the leaf hubs shift the communication data in thedata caches by means of shifters, distribute communication data withpreset bandwidth to each of leaf tiles, and then output to two leaftiles in each group of leaf tiles via two output ports, so as to achievemulticast communication through the communication method. FIG. 9illustrates a schematic diagram of an action of the hub not in directconnection with leaf tiles, and FIG. 10 illustrates a schematic diagramof an action of the hub in direct connection with leaf tiles. Controlsignals of hub one to two in all hubs not in direct connection with leaftiles are forwarded directly, and control signals of hub_one_to_two inhubs in direct connection with leaf tiles are forwarded after shifting,such that in the hubs in direct connection with leaf tiles, shifting canbe performed depending on data bits actually required for different leaftiles in accordance with numbers of the leaf tiles to allow the leaftiles to receive the desired data. In the H-tree structure, thetransmission order of data is as follows: from a central tile to ahub_0_0; from the hub_0_0 to a hub_1_x; from the hub_1_x to a hub_2_x;from the hub_2_x to a hub_3_x; and from the hub_3_x to leaf tiles.

When transmitting communication data from the plurality of leaf tiles tothe central tile, if the leaf tiles transmit full bandwidthcommunication data, the transmission manner of the communication datafrom the plurality of leaf tiles on the hubs is as follows: firstlyinputting into data caches of leaf hubs in direct connection with theleaf tiles, then transmitting in data caches of central hubssequentially, and finally inputting into a data cache of a central hubin direct connection with the central tile, wherein the central hubs sumup all received data transmitted from the leaf tiles by means of anadder, and output a result to the central tile via output ports, so asto achieve full bandwidth data communication from the plurality of leaftiles to the central tile. FIG. 11 illustrates a schematic diagram of anaction of the hub when outputs of the multiple cores are added andtransmitted to one core. Since it is two-to-one transmission, it onlyuses hub two to one in the hubs, and control signals of hub_two_to_onein all hubs are not shifted and masked, such that output data equal to asum of two groups of input data for each hub_two_to_one. FIG. 12illustrates a structure diagram of multicast transmission when outputsof the multiple cores are added and transmitted to one core in theH-tree structure. In the H-tree structure, the transmission order ofdata is as follows: from leaf tiles to a hub_3_x; from the hub_3_x to ahub_2_x; from the hub_2_x to a hub_1_x; from the hub_1_x to a hub_0_0;and from the hub_0_0 to a central tile.

When transmitting communication data from the plurality of leaf tiles tothe central tile, if the leaf tiles transmit communication data withrespective preset bandwidth, the transmission manner of thecommunication data from the plurality of leaf tiles on the hubs is asfollows: firstly inputting into data caches of leaf hubs in directconnection with the leaf tiles, then transmitting in data caches ofcentral hubs sequentially, and finally inputting into a data cache of acentral hub in direct connection with the central tile, wherein thecentral hubs shift all received data transmitted from the leaf tiles bymeans of shifters according to a position of preset bandwidth in fullbandwidth, then sum up all received data transmitted from the leaf tilesby means of an adder, and finally output a result to the central tilevia output ports, so as to achieve data communication with respectivepreset bandwidth from the plurality of leaf tiles to the central tile.FIG. 13 illustrates a schematic diagram of an action of the hub not indirect connection with leaf tiles when outputs of the multiple cores arebit spliced and transmitted to one core, and FIG. 14 illustrates aschematic diagram of an action of the hub in direct connection with leaftiles when outputs of the multiple cores are bit spliced and transmittedto one core. Since it is two-to-one transmission, it only useshub_two_to_one in the hubs; control signals of hub_two_to_one in allhubs are shifted and masked according to input signals, such that outputdata equal to a sum of two groups of input data for each hub_two_to_one;such that shifting can be performed depending on spliced bit numberresulted from splicing in accordance with numbers of the leaf tiles toshift with data bits actually required. In the H-tree structure, thetransmission order of data is as follows: from leaf tiles to a hub_3_x;from the hub_3_x to a hub_2_x; from the hub_2_x to a hub_1_x; from thehub_1_x to a hub_0_0; and from the hub_0_0 to a central tile.

Another embodiment is an apparatus in X-tree structure fornetwork-on-chip communication, comprising: a central tile that is acommunication data center of a network-on-chip; and a plurality of leaftiles that are communication data nodes of the network-on-chip and incommunication connection with the central tile by means of hubs, whereinthe communication connection is set as follows: every four leaf tilesare set as one group, the central tile is individually in communicationconnection with each group of leaf tiles (which include devices relatingto data operation, storage and transmission such as an arithmetic unit,a rain, a controller, etc.) by means of the hubs, and the connectingmanner can achieve efficient communication.

The communication structure is an X-tree fractal-tree structure. Acommunication structure constituted by each group of leaf tiles hasself-similarity, i.e., it is also a X-tree structure. It uses onecentral tile (which includes devices relating to data operation, storageand transmission such as an arithmetic unit, a rain, a controller, etc.,wherein the controller is a main controller for controlling datatransmission and operation of the leaf tiles). The setting manner of thenodes facilitates reducing complexity of connection, and is convenientfor setting and use of the network-on-chip structure. FIG. 16illustrates a structure diagram of a multicore on chip with (64+1) coresconnected using a X-tree, wherein sixty-four leaf tiles and one centraltile are connected using the X-tree structure. In addition, it has aplurality of hubs for processing and distributing data, and realizestransmitting data from one core to multiple cores in a broadcast ormulticast form, and transmitting data of the multiple cores after addingor bit splicing (i.e., splicing to {leaf_tile_63 data, leaf_tile62_data,. . . , leaf_tile0_data}) to one core, wherein the number, function andstructure of the related body (i.e., cores to be connected) are notlimited.

The communication connection is set as follows: under the circumstanceof not affecting the central tile to be individually in communicationconnection with each group of leaf tiles, a sharing degree of the hub ismaximized, and the communication connection achieves effectivecommunication of a plurality of nodes, decreases the number of hubs, andreduces complexity of the communication connection, wherein the H-treeis used for connecting respective tiles and is consisted of connectinglines and the hubs among the tiles. FIG. 17 illustrates a structurediagram of a hub in this embodiment. The hub is consisted of a pluralityof hub_one_to_four and a plurality of hub_four_to_one, wherein thehub_one_to_four divides one group of input into four groups of outputsfor transmitting from the central tile to the leaf tiles; and thehub_four_to_one merges four groups of inputs into one group of outputfor transmitting from the leaf tiles to the central tile.

FIG. 18 illustrates a structure diagram of the hub_one_to_four. Thehub_one_to_four is responsible for processing one group of input dataand forwarding the processed data to four output ports according tocontrol signals, and comprises an input data cache for caching inputdata; and shifters for shifting the input data according to the controlsignals and generating output data.

FIG. 19 illustrates a structure diagram of the hub_four_to_one. Thehub_four_to_one is responsible for processing four groups of input dataand forwarding the processed data to one output port according tocontrol signals, and comprises shifters for shifting the input dataaccording to the control signals; Mask logics for generating a 01 stringhaving the same bit number as the input data according to the controlsignals, and performing an AND operation on the 01 string and the inputdata; an adder for adding the four groups of input data; and an outputdata cache for caching output data. A communication method of theapparatus comprises: broadcasting or multicasting from the central tileto the plurality of leaf tiles; or transmitting the communication datafrom the plurality of leaf tiles to the central tile, which provides atechnical support for efficient broadcast or multicast.

When broadcasting from the central tile to the plurality of leaf tiles,the transmission manner of the communication data from the central tileon the hubs is as follows: firstly inputting into a data cache of acentral hub in direct connection with the central tile, thentransmitting in data caches of central hubs sequentially, and finallyinputting into data caches of leaf hubs in direct connection with theleaf tiles, wherein the leaf hubs output the communication data to fourleaf tiles in each group of leaf tiles via four output ports directly,so as to realize broadcast communication via the hubs and the tiles.FIG. 20 illustrates a schematic diagram of an action of the hub whenbroadcasting from one core to multiple cores. Since it is one-to-fourtransmission, it only uses hub_one_to_four in the hubs, and controlsignals of hub one_to_four in all hubs are forwarded directly, such thatoutput data equal to input data for each hub_one_to_four. FIG. 21illustrates a structure diagram of transmission from one core tomultiple cores in the X-tree structure. In this structure, thetransmission order of data is as follows: from a central tile to ahub_0_0; from the hub_0_0 to a hub_1_x; from the hub_1_x to a hub_2_x;and from the hub_2_x to leaf tiles.

When multicasting from the central tile to the plurality of leaf tiles,the transmission manner of the communication data from the central tileon the hubs is as follows: firstly inputting into a data cache of acentral hub in direct connection with the central tile, thentransmitting in data caches of central hubs sequentially, and finallyinputting into data caches of leaf hubs in direct connection with theleaf tiles, wherein the leaf hubs shift the communication data in thedata caches by means of shifters, distribute preset bandwidthcommunication data to each of leaf tiles, and then output to four leaftiles in each group of leaf tiles via four output ports, so as torealize multicast communication through the communication method. FIG.22 illustrates a schematic diagram of an action of the hub not in directconnection with leaf tiles, and control signals of the shownhub_one_to_four are forwarded directly; FIG. 23 illustrates a schematicdiagram of an action of the hub in direct connection with leaf tiles,and control signals of the shown hub one to four are forwarded aftershifting, such that in the hubs in direct connection with leaf tiles,shifting can be performed depending on data bits actually required fordifferent leaf tiles in accordance with numbers of the leaf tiles toallow the leaf tiles to receive the desired data. FIG. 21 illustrates astructure diagram of transmission from one core to multiple cores in aX-tree structure. In this structure, the transmission order of data isas follows: from a central tile to a hub_0_0; from the hub_0_0 to ahub_1_x; from the hub_1_x to a hub_2_x; and from the hub_2_x to leaftiles.

When transmitting communication data from the plurality of leaf tiles tothe central tile, if the leaf tiles transmit full bandwidthcommunication data, the transmission manner of the communication datafrom the plurality of leaf tiles on the hubs is as follows: firstlyinputting into data caches of leaf hubs in direct connection with theleaf tiles, then transmitting in data caches of central hubssequentially, and finally inputting into a data cache of a central hubin direct connection with the central tile, wherein the central hubs sumup all received data transmitted from the leaf tiles by means of anadder, and output a result to the central tile via output ports, so asto realize full bandwidth data communication from the plurality of leaftiles to the central tile. FIG. 24 illustrates a schematic diagram of anaction of the hub when outputs of the multiple cores are added andtransmitted to one core. Since it is four-to-one transmission, it onlyuses hub_four_to_one in the hubs, and control signals of hub_four_to_onein all hubs are not shifted and masked, such that output data equal to asum of four groups of input data for each hub_four_to one. FIG. 25illustrates a structure diagram of transmission when outputs of themultiple cores are added and transmitted to one core in the X-treestructure. In this structure, the transmission order of data is asfollows: from leaf tiles to a hub_2_x; from the hub_2_x to a hub_1_x;from the hub_1_x to a hub_0_0; and from the hub_0_0 to a central tile.

When transmitting communication data from the plurality of leaf tiles tothe central tile, if the leaf tiles transmit communication data withrespective preset bandwidth, the transmission manner of thecommunication data from the plurality of leaf tiles on the hubs is asfollows: firstly inputting into data caches of leaf hubs in directconnection with the leaf tiles, then transmitting in data caches ofcentral hubs sequentially, and finally inputting into a data cache of acentral hub in direct connection with the central tile, wherein thecentral hubs shift all received data transmitted from the leaf tiles bymeans of shifters according to a position of preset bandwidth in fullbandwidth, then sum up all received data transmitted from the leaf tilesby means of an adder, and finally output a result to the central tilevia output ports, so as to realize data communication with respectivepreset bandwidth from the plurality of leaf tiles to the central tile.Since it is four-to-one transmission, it only uses hub_four_to one inthe hubs. FIG. 26 illustrates a schematic diagram of an action of thehub not in direct connection with leaf tiles when multiple outputs arebit spliced and transmitted to one core, and control signals ofhub_four_to_one in all hubs are not shifted and masked, such that outputdata equal to a sum of four groups of input data for eachhub_four_to_one. FIG. 27 illustrates a schematic diagram of an action ofthe hub in direct connection with leaf tiles when multiple outputs arebit spliced and transmitted to one core, and control signals ofhub_four_to_one in all hubs are shifted and masked according to inputsignals, such that output data equal to a sum of four groups of inputdata for each hub_four_to_one, and shifting can be performed dependingon spliced bits spliced for different leaf tiles in accordance withnumbers of the leaf tiles to shift data bits actually required. FIG. 25illustrates a structure diagram of transmission when outputs ofsixty-four leaf tiles are added and transmitted to one central tile inthe X-tree structure. In this X-tree structure, the transmission orderof data is as follows: from leaf tiles to a hub_2_x; from the hub_2_x toa hub_1_x; from the hub_1_x to a hub_0_0; and from the hub_0_0 to acentral tile.

After the central hubs shift all received data transmitted from the leaftiles by means of shifters according to a position of preset bandwidthin full bandwidth, data beyond the preset bandwidth of the datatransmitted from each of the leaf tiles are set to 0 by means of fixedlogic units in the central hubs to execute subsequent summationoperation, and an efficient communication mode with small occupied areais achieved. FIG. 15 illustrates the first embodiment, i.e., a schematicdiagram of implementing bit splice in the H-tree structure. A bit widthof input data is the same as a bit width of output spliced data, butonly a part of input data is required for bit splice. In thisembodiment, firstly data of the leaf tiles are shifted in the hubs indirect connection with the leaf tiles to a final position, mask at otherpositions is set to be 0, and two inputs are added in all hubs. FIG. 28illustrates the second embodiment, i.e., a schematic diagram ofimplementing bit splice in the X-tree structure. A bit width of inputdata is the same as a bit width of output spliced data, but only a partof input data is required for bit splice. In this embodiment, firstlydata of the leaf tiles are shifted in the hubs in direct connection withthe leaf tiles to a final position, mask at other positions is set to be0, and four inputs are added in all hubs.

The apparatus and processing scale explained here are to simplify thepresent invention. Applications, modifications and variations of thefractal-tree structural network-on-chip communication apparatus andcommunication method of the present invention are obvious for thoseskilled in the art.

According to the disclosure, since it provides a fractal-treenetwork-on-chip communication apparatus and communication method, it canachieve broadcast and multicast operations on the network-on-chip in amanner of low delay, low complexity and small occupied area, so it has amanner of low delay, low complexity and small occupied area to achievebroadcast and multicast operations on the network-on-chip, and improvesbroadcast communication and multicast communication efficiency to obtaina better communication effect. Although the embodiments of the presentinvention have been disclosed above, they are not limited toapplications listed in the Description and embodiments, and they can befully adapted to various fields suitable for the present invention. Asfor those skilled in the art, additional modifications can be easilyachieved. Therefore, without departing from the claims and generalconcepts defined within the equivalent range, the present invention isnot limited to specific details and examples shown and described above.

INDUSTRIAL APPLICABILITY

The present invention can realize broadcast and multicast operations onthe network-on-chip in a manner of low delay, low complexity and smalloccupied area; can improve broadcast communication and multicastcommunication efficiency to obtain a better communication effect Thepresent invention solves the problem of broadcast and multicasttransmission among multiple cores on the chip in the same circuitthrough a fractal-tree means. Taking the H-tree structure for example,as for transmission among (n+1) cores, transmission delay has only logncycle; and as for transmission of data having a width of n, a data widthfor transmitting is also only n. The present invention also solves theproblem of more-to-one transmission among multiple cores on the chip inthe same circuit through a fractal-tree means, Taking the H-treestructure for example, as for transmission among (n+1) cores,transmission delay has only logn cycle; and as for transmission of datahaving a width of n, a data width for transmitting is also only n.

1. A fractal-tree communication structure for network-on-chip,comprising: a central node that is a communication data center of thenetwork-on-chip and used for broadcasting or multicasting communicationdata to a plurality of leaf nodes; a plurality of leaf nodes that arecommunication data nodes of the network-on-chip and used fortransmitting the communication data to a central node; and forwardermodules for connecting the central node with the plurality of leaf nodesand forwarding the communication data, wherein the plurality of leafnodes are divided into N groups, each group having the same number ofleaf nodes, wherein the central node is in communication connection witheach group of leaf nodes by means of the forwarder modules individually,wherein the communication structure is a fractal-tree structure, whereinthe communication structure constituted by each group of leaf nodes hasself-similarity, and wherein the forwarder modules comprise a centralforwarder module, leaf forwarder modules, and intermediate forwardermodules.
 2. The fractal-tree communication structure for network-on-chipaccording to claim 1, wherein under the circumstance of ensuring thatthe central node is in communication connection with each group of theleaf nodes individually, the number of the forwarder modules isdecreased, such that a sharing degree of the forwarder modules ismaximized.
 3. A communication method for a fractal-tree communicationstructure for network-on-chip the fractal-tree communication structurecomprising: a central node that is a communication data center of thenetwork-on-chip and used for broadcasting or multicasting communicationdata to a plurality of leaf nodes; a plurality of leaf nodes that arecommunication data nodes of the network-on-chip and used fortransmitting the communication data to a central node; and forwardermodules for connecting the central node with the plurality of leaf nodesand forwarding the communication data, wherein the plurality of leafnodes are divided into N groups, each group having the same number ofleaf nodes, wherein the central node is in communication connection witheach group of leaf nodes by means of the forwarder modules individually,wherein the communication structure is a fractal-tree structure, whereinthe communication structure constituted by each group of leaf nodes hasself-similarity, and wherein the forwarder modules comprise a centralforwarder module, leaf forwarder modules, and intermediate forwardermodules, the communication method comprising broadcasting ormulticasting communication data to the plurality of leaf nodes by meansof the central node, receiving the communication data in thenetwork-on-chip by the plurality of leaf nodes and transmitting thereceived communication data to the central node.
 4. The communicationmethod for a network-on-chip according to claim 3, comprising: whencommunication data is broadcasted from the central node to the pluralityof leaf nodes, firstly inputting the communication data into a datacache of the central forwarder module of the central node, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into data caches of the leaf forwarder modules of the leaf nodes,wherein the leaf forwarder modules output the communication data to theleaf nodes in each group of leaf nodes via output ports.
 5. Thecommunication method for a network-on-chip according to claim 3,comprising: when the central node multicasts communication data to theplurality of leaf nodes, firstly inputting the communication data into adata cache of the central forwarder module of the central node, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into data caches of the leaf forwarder modules in direct connectionwith the leaf nodes, wherein the leaf forwarder modules shift thecommunication data in the data cache by means of shifters, distributecommunication data with a preset bandwidth to each of leaf nodes, andoutput the communication data to the leaf nodes in each group of leafnodes via output ports of the leaf forwarder modules.
 6. Thecommunication method for a network-on-chip according to claim 3,comprising: when the plurality of leaf nodes transmit communication datato the central node, if the leaf nodes transmit full bandwidthcommunication data, firstly inputting the communication data into datacaches of the leaf forwarder modules of the leaf nodes, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into a data cache of the central forwarder module of the centralnode, wherein the central forwarder module sums up all received datatransmitted from the leaf nodes by means of an adder, and outputs aresult to the central node via output port of the central forwardermodule.
 7. The communication method for a network-on-chip according toclaim 3, comprising: when the plurality of leaf nodes transmitcommunication data to the central node, if the leaf nodes transmitcommunication data with respective preset bandwidth, firstly inputtingthe communication data into data caches of the leaf forwarder modules ofthe leaf nodes, then transmitting the communication data in data cachesof the intermediate forwarder modules sequentially, and finallyinputting the communication data into a data cache of the centralforwarder module of the central node, wherein the central forwardermodule shifts all received communication data transmitted from the leafnodes by means of shifters according to a position of the presetbandwidth in full bandwidth, sums up all received communication datatransmitted from the leaf nodes by means of an adder, and outputs aresult to the central node via output port of the central forwardermodule.
 8. The communication method for a network-on-chip according toclaim 7, comprising: after the central forwarder module shifts allreceived communication data transmitted from the leaf nodes by means ofshifters according to a position of the preset bandwidth in fullbandwidth, setting data beyond the preset bandwidth of the communicationdata transmitted from each of the leaf nodes to be 0 by means of fixedlogic units in the central forwarder module, to execute subsequentsummation operation.
 9. A communication method for a fractal-treecommunication structure for network-on-chip, the fractal-treecommunication structure comprising: a central node that is acommunication data center of the network-on-chip and used forbroadcasting or multicasting communication data to a plurality of leafnodes; a plurality of leaf nodes that are communication data nodes ofthe network-on-chip and used for transmitting the communication data toa central node; and forwarder modules for connecting the central nodewith the plurality of leaf nodes and forwarding the communication data,wherein the plurality of leaf nodes are divided into N groups, eachgroup having the same number of leaf nodes, wherein the central node isin communication connection with each group of leaf nodes by means ofthe forwarder modules individually, wherein the communication structureis a fractal-tree structure, wherein the communication structureconstituted by each group of leaf nodes has self-similarity, and whereinthe forwarder modules comprise a central forwarder module, leafforwarder modules, and intermediate forwarder modules; under thecircumstance of ensuring that the central node is in communicationconnection with each group of the leaf nodes individually, the number ofthe forwarder modules is decreased, such that a sharing degree of theforwarder modules is maximized; the communication method comprisingbroadcasting or multicasting communication data to the plurality of leafnodes by means of the central node, receiving the communication data inthe network-on-chip by the plurality of leaf nodes and transmitting thereceived communication data to the central node.
 10. The communicationmethod for a network-on-chip according to claim 9, comprising: whencommunication data is broadcasted from the central node to the pluralityof leaf nodes, firstly inputting the communication data into a datacache of the central forwarder module of the central node, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into data caches of the leaf forwarder modules of the leaf nodes,wherein the leaf forwarder modules output the communication data to theleaf nodes in each group of leaf nodes via output ports.
 11. Thecommunication method for a network-on-chip according to claim 9,comprising: when the central node multicasts communication data to theplurality of leaf nodes, firstly inputting the communication data into adata cache of the central forwarder module of the central node, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into data caches of the leaf forwarder modules in direct connectionwith the leaf nodes, wherein the leaf forwarder modules shift thecommunication data in the data cache by means of shifters, distributecommunication data with a preset bandwidth to each of leaf nodes, andoutput the communication data to the leaf nodes in each group of leafnodes via output ports of the leaf forwarder modules.
 12. Thecommunication method for a network-on-chip according to claim 9,comprising: when the plurality of leaf nodes transmit communication datato the central node, if the leaf nodes transmit full bandwidthcommunication data, firstly inputting the communication data into datacaches of the leaf forwarder modules of the leaf nodes, thentransmitting the communication data in data caches of the intermediateforwarder modules sequentially, and finally inputting the communicationdata into a data cache of the central forwarder module of the centralnode, wherein the central forwarder module sums up all received datatransmitted from the leaf nodes by means of an adder, and outputs aresult to the central node via output port of the central forwardermodule.
 13. The communication method for a network-on-chip according toclaim 9, comprising: when the plurality of leaf nodes transmitcommunication data to the central node, if the leaf nodes transmitcommunication data with respective preset bandwidth, firstly inputtingthe communication data into data caches of the leaf forwarder modules ofthe leaf nodes, then transmitting the communication data in data cachesof the intermediate forwarder modules sequentially, and finallyinputting the communication data into a data cache of the centralforwarder module of the central node, wherein the central forwardermodule shifts all received communication data transmitted from the leafnodes by means of shifters according to a position of the presetbandwidth in full bandwidth, sums up all received communication datatransmitted from the leaf nodes by means of an adder, and outputs aresult to the central node via output port of the central forwardermodule.
 14. The communication method for a network-on-chip according toclaim 13, comprising: after the central forwarder module shifts allreceived communication data transmitted from the leaf nodes by means ofshifters according to a position of the preset bandwidth in fullbandwidth, setting data beyond the preset bandwidth of the communicationdata transmitted from each of the leaf nodes to be 0 by means of fixedlogic units in the central forwarder module, to execute subsequentsummation operation.
 15. A control apparatus comprising a fractal-treecommunication structure for network-on-chip, the fractal-treecommunication structure comprising: a central node that is acommunication data center of the network-on-chip and used forbroadcasting or multicasting communication data to a plurality of leafnodes; a plurality of leaf nodes that are communication data nodes ofthe network-on-chip and used for transmitting the communication data toa central node; and forwarder modules for connecting the central nodewith the plurality of leaf nodes and forwarding the communication data,wherein the plurality of leaf nodes are divided into N groups, eachgroup having the same number of leaf nodes, wherein the central node isin communication connection with each group of leaf nodes by means ofthe forwarder modules individually, wherein the communication structureis a fractal-tree structure, wherein the communication structureconstituted by each group of leaf nodes has self-similarity, and whereinthe forwarder modules comprise a central forwarder module, leafforwarder modules, and intermediate forwarder modules; wherein thecontrol apparatus comprises one or more communication structuresconnected by means of forwarder modules.
 16. An intelligent chipcomprising the control apparatus, the control apparatus comprising afractal-tree communication structure for network-on-chip, thefractal-tree communication structure comprising: a central node that isa communication data center of the network-on-chip and used forbroadcasting or multicasting communication data to a plurality of leafnodes; a plurality of leaf nodes that are communication data nodes ofthe network-on-chip and used for transmitting the communication data toa central node; and forwarder modules for connecting the central nodewith the plurality of leaf nodes and forwarding the communication data,wherein the plurality of leaf nodes are divided into N groups, eachgroup having the same number of leaf nodes, wherein the central node isin communication connection with each group of leaf nodes by means ofthe forwarder modules individually, wherein the communication structureis a fractal-tree structure, wherein the communication structureconstituted by each group of leaf nodes has self-similarity, and whereinthe forwarder modules comprise a central forwarder module, leafforwarder modules, and intermediate forwarder modules.